Implement EVFILT_FS (partially)

CMakeLists.txt

@@ -76,6 +76,7 @@ else()
 		src/linux/read.c
 		src/linux/proc.c
 		src/linux/machport.c
+		src/linux/fs.c
 		src/common/*.h
 		src/common/filter.c
 		src/common/knote.c

src/common/filter.c

@@ -31,6 +31,7 @@ extern const struct filter evfilt_proc;
 extern const struct filter evfilt_timer;
 extern const struct filter evfilt_user;
 extern const struct filter evfilt_machport;
+extern const struct filter evfilt_fs;
 
 static int
 filter_register(struct kqueue *kq, short filter, const struct filter *src)
@@ -104,6 +105,7 @@ filter_register_all(struct kqueue *kq)
     rv += filter_register(kq, EVFILT_TIMER, &evfilt_timer);
     rv += filter_register(kq, EVFILT_USER, &evfilt_user);
     rv += filter_register(kq, EVFILT_MACHPORT, &evfilt_machport);
+    rv += filter_register(kq, EVFILT_FS, &evfilt_fs);
     kq->kq_nfds++;
     if (rv != 0) {
         filter_unregister_all(kq);
@@ -168,11 +170,12 @@ filter_name(short filt)
         "EVFILT_SIGNAL", 
         "EVFILT_TIMER", 
         "EVFILT_MACHPORT",
-        "EVFILT_FS",    
-        // "EVFILT_LIO",  
+        "EVFILT_FS",
         "EVFILT_USER",
-        // EVFILT_VM!
-        "EVFILT_NETDEV", 
+        "EVFILT_VM",
+        "EVFILT_SOCK",
+        "EVFILT_MEMORYSTATUS",
+        "EVFILT_EXCEPT",
     };
 
     id = ~filt;

src/linux/fs.c

@@ -0,0 +1,134 @@
+/*
+ * Copyright (c) 2017 Lubos Dolezel
+ *
+ * Permission to use, copy, modify, and distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+ * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+ * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+ * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ */
+
+#include <errno.h>
+#include <fcntl.h>
+#include <sys/ioctl.h>
+#include <pthread.h>
+#include <signal.h>
+#include <stdlib.h>
+#include <stdio.h>
+#include <sys/ioctl.h>
+#include <sys/queue.h>
+#include <sys/socket.h>
+#include <sys/types.h>
+#include <sys/mount.h>
+#include <string.h>
+#include <unistd.h>
+
+#include "private.h"
+
+int
+evfilt_fs_copyout(struct kevent64_s *dst, struct knote *src, void *ptr)
+{
+    struct epoll_event * const ev = (struct epoll_event *) ptr;
+
+    epoll_event_dump(ev);
+    kevent_int_to_64(&src->kev, dst);
+
+	// TODO: filter out events
+	// TODO: provide real event fflags
+	dst->fflags = VQ_MOUNT;
+
+    return (0);
+}
+
+int
+evfilt_fs_knote_create(struct filter *filt, struct knote *kn)
+{
+    struct epoll_event ev;
+
+    /* Convert the kevent into an epoll_event */
+    kn->data.events = EPOLLERR;
+    kn->kn_epollfd = filter_epfd(filt);
+
+    memset(&ev, 0, sizeof(ev));
+    ev.events = kn->data.events;
+    ev.data.ptr = kn;
+
+    kn->kdata.kn_dupfd = open("/proc/mounts", O_RDONLY);
+	if (kn->kdata.kn_dupfd == -1) {
+        dbg_printf("open /proc/mounts: %s", strerror(errno));
+        return (-1);
+	}
+
+    if (epoll_ctl(kn->kn_epollfd, EPOLL_CTL_ADD, kn->kdata.kn_dupfd, &ev) < 0) {
+        dbg_printf("epoll_ctl(2): %s", strerror(errno));
+        return (-1);
+    }
+    return 0;
+}
+
+int
+evfilt_fs_knote_modify(struct filter *filt, struct knote *kn, 
+        const struct kevent64_s *kev)
+{
+    return 0;
+}
+
+int
+evfilt_fs_knote_delete(struct filter *filt, struct knote *kn)
+{
+    if (kn->kev.flags & EV_DISABLE)
+        return (0);
+    else {
+        if (epoll_ctl(kn->kn_epollfd, EPOLL_CTL_DEL, kn->kdata.kn_dupfd, NULL) < 0) {
+            dbg_perror("epoll_ctl(2)");
+            return (-1);
+        }
+        (void) close(kn->kdata.kn_dupfd);
+        kn->kdata.kn_dupfd = -1;
+        return 0;
+    }
+}
+
+int
+evfilt_fs_knote_enable(struct filter *filt, struct knote *kn)
+{
+    struct epoll_event ev;
+
+    memset(&ev, 0, sizeof(ev));
+    ev.events = kn->data.events;
+    ev.data.ptr = kn;
+
+	if (epoll_ctl(kn->kn_epollfd, EPOLL_CTL_ADD, kn->kdata.kn_dupfd, &ev) < 0) {
+		dbg_perror("epoll_ctl(2)");
+		return (-1);
+	}
+	return (0);
+}
+
+int
+evfilt_fs_knote_disable(struct filter *filt, struct knote *kn)
+{
+	if (epoll_ctl(kn->kn_epollfd, EPOLL_CTL_DEL, kn->kdata.kn_dupfd, NULL) < 0) {
+		dbg_perror("epoll_ctl(2)");
+		return (-1);
+	}
+	return (0);
+}
+
+const struct filter evfilt_fs = {
+    EVFILT_MACHPORT,
+    NULL,
+    NULL,
+    evfilt_fs_copyout,
+    evfilt_fs_knote_create,
+    evfilt_fs_knote_modify,
+    evfilt_fs_knote_delete,
+    evfilt_fs_knote_enable,
+    evfilt_fs_knote_disable,         
+};